The present invention pertains generally to flow control structures and mechanisms and, more particularly, to control of water flow between fluidly connected chambers of automated brewing machines.
Automated brewing machines such as coffee and tea makers typically have a brewing water reservoir wherein water is heated by a heating element inside of or in contact with the reservoir. Heated water is then transferred from the reservoir, typically by thermal expansion or displacement, to a brewing chamber or basket which holds a brewing material such as coffee grounds or tea leaves, through which the heated water flows to produce a brewed beverage which drains into a carafe or pitcher positioned underneath the brewing chamber.
The rate of flow of heated water through the brewing material in the brewing chamber directly affects the content and taste of the brewed beverage. For example, a relatively fast rate of flow of hot water through coffee grounds in the brewing chamber will result in relatively diluted coffee with relatively less flavor and caffeine, than is produced by a slower rate of flow. And to correctly brew decaffeinated coffee grounds, a relatively slower rate of flow should be used in order to achieve a taste comparable to xe2x80x9cregularxe2x80x9d or caffeinated coffee which is brewed with a relatively faster rate of flow. In a displacement style brewing machine, the rate at which the heated water flows into the brewing chamber is primarily a function of the rate at which water is introduced to the reservoir, the size of the conduit or passage between the reservoir and the brewing chamber, and the size of holes in a water distributor or showerhead over the brewing chamber. The rate of flow through the brewing chamber is also a function of the size of the drainage hole at bottom of the basket. These dimensions are typically fixed, leaving no practical means for adjusting the rate of flow for brewing different types of beverages.
Some attempts have been made to enable adjustment of flow rate by, for example, providing an adaptable, interchangeable showerhead with different hole sizes; but this approach is cumbersome, labor-intensive, and dependent upon availability of the part or parts to be interchanged. Reduced-opening showerheads may not provide optimal water distribution over the brewing material in the brewing chamber. Furthermore, showerhead flow rate adjustment does not address the rate of flow into the reservoir.
Another operational difficulty associated with automated brewing machines is that the brewing cycle, i.e., the heating of water in the reservoir and flow through and out of the brewing chamber, may commence immediately upon introduction of additional water into the reservoir. This is especially the case in the well-known displacement type brewing machine, wherein a charge of hot brewing water sits in wait in the reservoir to be displaced into the brewing basket immediately upon introduction of additional water from a separate filling chamber connected to the reservoir. This necessitates that a carafe or pitcher be positioned underneath the brewing chamber as water is added to the filling chamber. Thus a second pitcher is needed to measure and pour water into the reservoir. The requirement of a separate filling pitcher is burdensome, especially in the context of machines designed primarily for domestic use.
U.S. Pat. No. 5,251,541 describes a displacement type brewing machine wherein a stopper directly engages a fill port between a fill basin and a heating reservoir when water is being added to the fill basin. The stopper is connected to one end of a pivotal arm. The other end of the pivotal arm may be contacted by a cam on a shaft which depends from a lid selectively covering an opening to the fill basin. When the lid is in the closed position, the cam on the shaft contacts the other end of the arm to thereby pivot that arm and lift the stopper out of engagement with the fill port, allowing water to drain through the fill port into the reservoir. When the lid is opened by swinging it to the side, the cam is moved out of contact with the arm, allowing the arm to pivot in the opposite direction so that the stopper directly engages and covers the fill port. While this structure accomplishes suspension of the brewing cycle until the lid on the fill tray is closed, it does not allow any variable rate flow control mechanism to be incorporated into or associated with the fill port, as the stopper must be positioned directly over the fill port.
The present invention overcomes these and other disadvantages of the prior art by providing an automated brewing machine having multiple brewing water flow control mechanisms which control commencement of a brewing cycle and which control the rate of brewing water flow and ultimately the rate of brewing and the resultant content and taste of brewed beverages, such as caffeinated or decaffeinated coffee.
In accordance with one aspect of the invention, there is provided an automated brewing machine for brewing a quantity of brewed beverage by directing a flow of heated water over a brewing material, the brewing machine having a reservoir for holding brewing water and a heating element in thermal communication with the reservoir for heating brewing water within the reservoir; a filling chamber which is fluidly connected to the reservoir whereby water in the filling chamber can flow into the reservoir, and an adjustable flow rate control valve assembly between the filling chamber and the reservoir, whereby a rate of flow of water from the chamber to the reservoir can be adjusted, and a brewing chamber fluidly connected to the reservoir.
In accordance with another aspect of the invention, there is provided a brewing machine for preparing a brewed beverage by establishing a flow of heated water through a brewing material, the machine having a filling chamber for initially receiving brewing water into the machine, the filling chamber having a cover with an openable lid; a heating reservoir fluidly connected to a hole in the filling chamber through which water in the filling chamber enters the reservoir, and a heat source in thermal communication with the heating reservoir; a control chamber which surrounds the hole in the filling chamber, and a movable seal engageable with an opening in the control chamber which controls flow of water from the filling chamber to the reservoir.
In accordance with still another aspect of the invention, there is provided a controllable adjustable flow rate brewing device having multiple chambers including a filling chamber, a control chamber, a heating chamber and a brewing chamber. The control chamber is positioned above a drain hole which provides a fluid connection between the control chamber and the heating chamber. The control chamber has an opening between the control chamber and the filling chamber. A seal is engageable and disengageable with the control chamber opening and is activated by a lid which covers the filling chamber. A flow rate control valve at least partially within the control chamber is operative to control a rate of flow through the drain hole and into the heating chamber.
In accordance with still another aspect of the invention, a flow rate control valve for selecting the brewing cycle and water flow rate through the system has an easily accessible dial for ready selection by the user. This flow rate control valve can also be adapted to have an additional fill position in which the drain is closed by the valve when water is added to the filling chamber.
And in accordance with still another aspect of the invention, brewing chamber showerhead flow control rate assemblies are provided which enable adjustment of the flow rate of brewing water through a showerhead which distributes heated brewing water into a brewing chamber which holds a brewing material. The showerhead flow rate control assemblies can be employed in combination with the other flow control and flow rate control mechanisms of the invention.
These and other aspects of the present invention are herein described in particularized detail with reference to the accompanying Figures.